Waiter v



W, V. TURNER.

FLUID PRESSURE BRAKE. APPLlCATION' FILED NOV. 4. 1916.

1,312,649 Patented Aug. 12, 1919.

INVENTOFI Wan-6w. Turner NT @FJFICJE.

. WALT R v. TURNER, O-FIWILKINSBURG, PENNsYLvANm, ASSIGNOR TO THE WESTING- 'a citizen of the United States, 'lVilkinsburg, in the. county ofAllegheny HOUSE AIR BRAKE coMPANY, 0E PENNSYLVANIA.

v FLUID-PRESSURE BRAKE.

Specification 'of Letters Fatent.

0F WILMERDING, PENNsYLvA IA, a oonPoEA'rro PatentedAug. 12, 11919.

Application filed Novembere, 1916. Serial No. 129,439.

To all whom it may concern:

Be it known. that I, WAL ER V. T RNE and State of Pennsylvania, have invented new and useful Improvements" in Fluid- Pressure Brakes,

of which the following is a specification. This invention relates, to fluid-pressure brakes, and more particularly to the con: struction of the brake cylinder portion of the brake apparatus. w

The usual standard fluid pressure brake apparatus is calculated and designed so as to produce a predetermined pressure in the brake cylinder for a given reduction in brake pipe pressure, the brake cylinder piston travel being assumed as a predetermined amount, for example, eight inches.

There is usually more or less false piston ging and the like, and if the brake rigging be not rigid enoughfthis spring action is liabletobe excessive and may cause the brake cylinder piston to strike the non-pressure head of the brake cylinder where the brakes are applied with force. In order to prevent this, it has been proposed to limit the piston travel as adjusted by the. slack adjusterto less than the calculated piston five inches, in order to insure that the piston will not strike the cylinder head by reason of the falsepiston travel even when the brakes are heavily ap- "plied. I

If, however, this is done, then, since the effective .volume of the brake cylinder has been reduced by-reason of the shorter piston travel, the brake cylinder pressureobtained fora given reduction in brake pipe pressure will exceed the calculated amountand Wlll be excessive in many cases.

In order to remedy the last mentioned difiiculty,

tion is to provide means for excessive brake cylinder pressure, due to short piston travel, for a in brake pipe pressure. I preferably accomplish this object by lengthening the brake cylinder and by'providing for a lost motion of the brake cylinder piston, relative to thebrake rigging. v

In the accompanying drawing; Figure 1 given reduction residing at 'ing a hollow stem 4 within the principal object of my invena preventing an der embodying my improvement; and Fig.

2 a similar View, showing the brake cylinder piston with the'lost motion taken up.- According to myinvention, the brake cylinder .1 is made with a longer stroke than the standard. brake cylinder and contains theusual brakecylinder piston 2,'subject to the pressure of the release spring 3 and hav I which the piston rod '5 is contained. The piston rod 5 is connected to the usual ton, since the piston rod 5 is of. the usual length, while the-brake cylinder is of greater length, the collar, 6

If fluid under pressure is supplied to the brake cylinder to effect anapplication of the brakes, the brake cylinder piston 2 first moves out to the position shown in Fig. 2 of the drawing, in which the piston engages the end of the rod is then actuated by the further movement of the brake cylinder piston t apply the brakes. If it be assumed that the slack adjuster is set for a piston travel of five inches and that the. lost motion of the brake cylinder piston is threeinches, then. the brake cylinder piston will move out eight inches for an effective brake ylinder piston travel of five inches.

- It will thus be seen that the brake cylinder pressure for a given reduction in brake pipe pressure can be made to correspond "with that obtained in the usual standard equipment for a given brake cylinder piston preventing further inward movement of the piston rod.

piston rod 5 and the piston brake rigging and is provided with a collar 6 adapted to engage the outerend ofthe plston 2 continues its movement to the pressure head 7 of the brake cylinder, so that the slack will be adjusted by the slack adjuster with reference to the effective brake cylinder piston travel instead of the actual piston travel.

Having now described my invention, what I claim as new and desire to secure by Let ters Patent is:

1. In a fluid pressure brake, the combina-- tion with an extended brake cylinder and a brake cylinder piston rod of the usual length, of a brake cylinder piston havinga preliminary movement relative to the piston rod in applying the brakes.

2. In a fluid pressure brake, the combination With a brake cylinder of a brake cylinder piston and a brake cylinder piston rod provided With a stop adapted to engage the brake cylinder for limitin the movement of the rod with respect to the brake cylinder movement of the rod to thereby permit an initial movement of the brake cylinder piston relative to the piston rod in applying the brakes.

In testimony whereof I hereunto set my hand.

VVAL'IER V. TURNER. 

